1. Field of the Invention
The present invention relates to a method and a device for detecting wear on at least one component of an electric bicycle.
2. Description of the Related Art
The present invention relates to a method for detecting wear on the chain drive of an electric bicycle, the chain drive including an electric motor driving at least one driveshaft equipped with at least one sprocket wheel, at least one output shaft, also equipped with at least one sprocket wheel, and at least one closed chain, which is guided over a sprocket wheel of the driveshaft and a sprocket wheel of the output shaft, so that the chain transmits the torque acting on the driveshaft to the output shaft.
Many components of a bicycle are not designed for durability but instead have only operational stability and therefore must be serviced regularly or even replaced. Thus, the brakes and the bicycle lights, for example, must be serviced regularly to ensure operational reliability of the bicycle. Other components, for example, the frame, are subject to wear or fatigue, which may result in impaired traffic safety of the bicycle. Service intervals are therefore stipulated for some bicycle components, for example, the brakes, the gearshift system and the bicycle fork. However, these fixed intervals are not adapted to the actual individual wear and stress on the bicycle.
The efficiency of the drive of an electric bicycle depends to a significant extent on the condition of the chain, the chain rings and pinions. In practice, bushed roller chains or bearing-collar chains are generally used as the bicycle chain. During operation, a wear-inducing friction occurs in the interior of the chain, in particular between the bushings or bearing collars and the corresponding rolls, resulting in an increase in the chain pitch and consequently a lengthening of the chain. Since the chain pitch is then no longer tailored to the tooth spacing of the sprocket wheels, i.e., the chain ring and pinion, there is a decline in torque transmission efficiency. Furthermore, the sprocket wheels are subject to increased wear. The wear depends to a significant extent on the degree of soiling of the chain and sprocket wheels because dirt acts like an abrasive. The pinion and chain rings may be used further only if the chain is changed promptly.
Therefore, not only do regular inspection and service of the chain affect the efficiency of the chain drive, but also the running performance of the chain and sprocket wheels may be significantly improved in this way.
Wear on the chain may be checked manually in the case of chain rings manufactured according to the standard. The wear limit has been reached if the chain may be lifted away from the gear rim by more than 5 mm, and the chain should be replaced. Wear testing may be carried out with the aid of a chain gauge, regardless of the type of chain ring. The length of the chain is measured over a defined number of chain links. Both methods are based on a manual inspection and cannot be carried out during ongoing operation, i.e., while cycling. These test methods require technical knowledge and are not necessarily carried out regularly.